mac802154: fix following checkpath.pl warning Prefer pr_warn(... to pr_warning(...

This patch fixes checkpath.pl:
 WARNING: Prefer pr_warn(... to pr_warning(...
 #447: FILE: ./wpan.c:447:
Signed-off-by: Weilong Chen <chenweilong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/mac802154/wpan.c

@@ -444,7 +444,7 @@ mac802154_subif_frame(struct mac802154_sub_if_data *sdata, struct sk_buff *skb)
 	case IEEE802154_FC_TYPE_DATA:
 		return mac802154_process_data(sdata->dev, skb);
 	default:
-		pr_warning("ieee802154: bad frame received (type = %d)\n",
+		pr_warn("ieee802154: bad frame received (type = %d)\n",
 			mac_cb_type(skb));
 		kfree_skb(skb);
 		return NET_RX_DROP;